Pre-formed objects

ABSTRACT

Disclosed is a continuous line process for making a pre-formed object having a plurality of surfaces comprising the steps of:
         (1) providing a sol phase of the composition comprising a solvent and a gelling agent having a sol-gel transition point between about the melting point of the solvent and about the boiling point of the solvent;   (2) forming surfaces of the sol phase composition by passing through a surface forming system, the surface forming system pressing the sol phase composition between a plurality of liners;   (3) cooling the sol phase composition into a gel phase; and   (4) cutting the gel phase composition;   wherein the pre-formed object is free of a supporting substrate.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Divisional application of application Ser. No.10/316,639, filed Dec. 11, 2002 now U.S. Pat. No. 6,899,840, and claimsthe benefit of priority to U.S. Provisional Application No. 60/339,287,filed Dec. 11, 2001.

FIELD

The present invention relates to a continuous line process for making apre-formed object, which is free of a supporting substrate, made of acomposition comprising a solvent and a gelling agent having a sol-geltransition point between about the melting point of the solvent andabout the boiling point of the solvent. The process is suitable forproviding stable pre-formed objects in large scale manufacturing.

BACKGROUND

Pre-formed objects made of gelling agents, which are free of supportingsubstrates, provide unique benefits to various consumer products due toits formed, yet flexible physical characteristics. Pre-formed patch andmask devices are useful for cosmetic and dermatological treatmentproducts such as for delivering skin care actives, percutaneouslydeliverable pharmaceuticals, and for promoting healing of burns orwounds. Edible pre-formed sheets and objects provide nutritionalproducts and snacks having distinctive appearance and oral texture, andoral administrative pharmaceuticals.

Co-pending PCT application US/00/09694 relates to a pre-formed cosmeticdevice for delivering skin benefit agents to the skin, hair or nails,the cosmetic device comprising a solid gel sheet having opposed firstand second surfaces, wherein the gel sheet comprises one or more gellingagents and topical acceptable hydrophilic solvent. In PCT applicationUS/00/09694, injection molding is disclosed as a preferred embodimentfor producing the gel sheet.

While injection molding is one effective method to provide pre-formedobjects, particularly in small scale production, such method is notdesirable for producing large quantities of pre-formed objects due tothe complexity of instruments required to form the composition atcontrolled temperatures and speed. Further, in that forming ofcompositions containing gelling agents by injection molding requireflash cooling of the composition, this may result in compositions thatdo not have a stable rheology. Unstable rheology of a pre-formed objecthaving no supporting substrate may lead to unstableness of the form ofthe product, leaking of the product from the packaging, or ineffectivedelivery of actives via the product. All of such may significantlyaffect product performance and/or aesthetics.

Based on the foregoing, there is a need for a process for producing astable pre-formed object which is free of a supporting substrate thatcan be applied to large scale manufacturing.

None of the existing art provides all of the advantages and benefits ofthe present invention.

SUMMARY

The present invention is directed to a continuous line process formaking a pre-formed object having a plurality of surfaces comprising thesteps of:

-   -   (1) providing a sol phase of the composition comprising a        solvent and a gelling agent having a sol-gel transition point        between about the melting point of the solvent and about the        boiling point of the solvent;    -   (2) forming surfaces of the sol phase composition by passing        through a surface forming system, the surface forming system        pressing the sol phase composition between a plurality of        liners;    -   (3) cooling the sol phase composition into a gel phase; and    -   (4) cutting the gel phase composition;    -   wherein the pre-formed object is free of a supporting substrate.

The process provides a process, particularly suitable for large scalemanufacturing, for producing a stable pre-formed object which is free ofa supporting substrate.

The present invention is further directed to a pre-formed object made bythe process above.

The present invention is further directed to a use of the pre-formedobject made by the process above as a cosmetic product, a pharmaceuticalproduct, or a food product.

The present invention is further directed to a cosmetic devicecomprising the pre-formed object made by the process above and a coatingcomposition.

The present invention is further directed to a cosmetic devicecomprising a pre-formed sheet having a first surface having a specifiedtexture, and a coating composition of a specified viscosity.

These and other features, aspects, and advantages of the presentinvention will become better understood from a reading of the followingdescription, and appended claims.

BRIEF DESCRIPTION OF THE FIGURES

While the specification concludes with claims particularly pointing outand distinctly claiming the invention, it is believed that the presentinvention will be better understood from the following description ofpreferred, nonlimiting embodiments and representations taken inconjunction with the accompanying drawings in which:

FIG. 1 is a schematic view of a preferred embodiment of the process ofthe present invention.

FIG. 2 is another schematic view of a preferred embodiment of theprocess of the present invention.

FIG. 3 is a schematic view of a preferred embodiment of the surfaceforming system of the present invention.

FIG. 4 is a schematic view of a preferred embodiment of the cuttingsystem of the present invention.

FIG. 5 is a perspective view of a preferred embodiment of the pre-formedsheet of the present invention.

FIG. 6 is an enlarged, partially segmented perspective view of the firstsurface vicinity of a preferred embodiment of the pre-formed sheet ofthe present invention.

FIG. 7 is a sectional view of a preferred embodiment of the cosmeticdevice of the present invention.

FIG. 8 is a schematic view of a set up for measuring flex angle.

DEFINITIONS

All cited references are incorporated herein by reference in theirentireties. Citation of any reference is not an admission regarding anydetermination as to its availability as prior art to the claimedinvention.

Herein, “comprising” means that other steps and other ingredients whichdo not affect the end result can be added. This term encompasses theterms “consisting of” and “consisting essentially of”.

All percentages, parts and ratios are based upon the total weight of thecompositions of the present invention, unless otherwise specified. Allsuch weights as they pertain to listed ingredients are based on theactive level and, therefore, do not include carriers or by-products thatmay be included in commercially available materials. All measurementsare conducted at 25° C. unless otherwise specified.

All ingredients such as actives and other ingredients useful herein maybe categorized or described by their cosmetic and/or therapeutic benefitor their postulated mode of action. However, it is to be understood thatthe active and other ingredients useful herein can, in some instances,provide more than one cosmetic and/or therapeutic benefit or operate viamore than one mode of action. Therefore, classifications herein are madefor the sake of convenience and are not intended to limit an ingredientto the particularly stated application or applications listed.

The term “pre-formed” as used herein, means that the object ismanufactured into a form having a predetermined shape and size, whereinthe object may be removed from any associated packaging and placed ordraped onto the target surface by the fingers without furtherpreparative steps by the user. The term “pre-formed” also means that,when manufacturing is completed, the object substantially retains itsshape at the desired normal storage temperature when lying on a flatsurface. The composition may nevertheless flex or be deformed whenapplied to an uneven surface or if impressed.

The term “free of supporting substrate” as used herein, means thepre-formed object is uniform and unilamellar in composition, with noadditional substrate or layer for aiding in the structure or integrityof the pre-formed object.

The term “sol phase composition” as used herein, means the compositionfor making the pre-formed object being in a sol phase state or anincomplete gel phase state during manufacturing.

The term “gel phase composition” as used herein, means the compositionfor making the pre-formed object being in a complete gel phase stateduring manufacturing.

The term “first surface” as used herein, means a lower surface of thepre-formed sheet during manufacturing, and after having been packaged.

The term “thickness” as used herein, means a thickness of a pre-formedsheet, wherein when the sheet is textured, the peaks of the texture areused for measuring the thickness.

The term “depth” as used herein, relates to a length in the thicknessdirection of a texture provided on the surface of a pre-formed sheet.

The term “frequency” as used herein, relates to the number of repeatingnon-planar topography per mm, the repetition of the non-planertopography providing a texture to the surface of a pre-formed sheet.

DETAILED DESCRIPTION

While the specification concludes with claims particularly pointing outand distinctly claiming the invention, it is believed that the presentinvention will be better understood from the following description.

Pre-Formed Object

The pre-formed object provides structure and shape, allowing it to behandled and to suit treatment of a specific target area of the skin,hair or nails, or to be orally administered or consumed. It can also actas a reservoir or as a delivery vehicle for skin benefit agents and,when applied to the skin, hair or nails, by virtue of evaporation of asolvent from the pre-formed object, provide a cooling action to theobject during use. The pre-formed object may be utilized for a cosmeticproduct, a pharmaceutical product, or a food product, by itself, or incombination with other materials.

The pre-formed object is free of a supporting substrate. The existenceof a supporting substrate provides various advantages duringmanufacture, by giving flexibility and strength to the pre-formedobject, and allowing ease of cutting the pre-formed object. The processof the present invention provides a suitable method of producingpre-formed objects without the aid of a supporting substrate.

The pre-formed objects have a plurality of surfaces that arecontinuously formed by pressing the sol phase composition againstliners, and then cut, to form a pre-determined size and shape. Theprocess herein can make any shape of object that is obtained by cuttinga continuous flow of material. Objects that are advantageously made bythe process herein include sheets, half-cylinders, and cylinders, andparticularly such objects that are textured on at least one surface.When the pre-formed object is for topical application, the size andshape are adapted to conform to a desired target area which could be thenails or cuticles, the hair or scalp, a human face or part thereof,legs, hands, arms, feet, or human torso. The exact size and shape willdepend upon the intended use and product characteristics.

Preferably, the pre-formed object has at least one surface textured.When the pre-formed object is a sheet, either or both of the first andsecond surfaces are textured. Preferably the first surface, or the lowersurface, is textured. The texture for the surfaces herein are useful forthe production process, the characteristic of the obtained product, orboth, preferably for both. The texturing of the surface is useful fordetermining and thus controlling the flow of the sol phase compositionwhen passing through the surface forming system and cooling step. Thetexturing of the surface may also provide various advantages to theobtained product. For example, the texturing may provide flexibility,ease of handling, more adhesion to the skin for dermal use, a matteappearance to the object, or distinct mouth feel for oral use. Theparticular characteristics for the cosmetic device herein are describedbelow. The design, depth, and frequency of the texture is selecteddepending on the need of the process and character of the product. Thetexture is typically a regular repetition of pattern, and can begeneralized across a certain area, provided only for a given area suchas the peripheral, or provided different textures depending on theregion. In a preferred pre-formed sheet embodiment, the texture isprovided to the entire area of the first surface, more preferably, thetexture is provided to the entire area of the first and second surfaces.

The pre-formed object made by the present invention is stable in morethan one aspect. The pre-formed object has a suitable gel strength and asuitable flexibility, both characteristics having improved consistencyover time at normal storage temperatures. Normal storage temperaturetypically refers to room temperature, preferably 25° C., however, whenthe pre-formed object is designed to be chilled or frozen on the shelffor display, stability should be assessed at the intended storagetemperature.

When the pre-formed object is made of a composition that may go undersyneresis, stability is also measured by the exudates produced by thepre-formed object over time. The pre-formed object made by the presentinvention produces less exudates than a composition made by, forexample, injection molding.

The composition for making the pre-formed objects comprise, as essentialcomponents, a solvent and a gelling agent having a sol-gel transitionpoint between about the melting point of the solvent and about theboiling point of the solvent. The weight percentage of components thatmake the composition are similar to that of the finally obtainedpre-formed object, with slight increase or decrease occurring during theprocess, for example, loss of weight of water due to evaporation, orgain of weight of water due to hygroscopic components. For convenience,the weight percentage of components are referred to in view of theentire weight of the starting sol phase composition for making thepre-formed object.

Solvent

The pre-formed objects of the present invention comprise a solvent forthe gelling agent. The solvent is selected so that a sol phase is madein combination with the gelling agent, wherein such sol phasetransitions into a gel phase between the melting point and boiling pointof the solvent. Typically the gelling agent is at least miscible in thesolvent at sol phase state for eventually providing a uniformunilamellar pre-formed object. The amount and type of solvent isdetermined to provide a stable gel phase with the gelling agent, in viewof the desired mechanical properties, particularly gel strength andflexibility, and also in view of the desired characteristic of theobtained product. Preferably, the solvent further acts as a plasticiseror softener for the pre-formed object.

or topical use, the pre-formed object comprises a hydrophilic solvent.The term “hydrophilic” as used in reference to solvents herein, meansthat the solvent is miscible with water, at least in a solvent to waterratio of 1 to 10, preferably 1 to 5. A topical acceptable, hydrophilicsolvent is one which can be used in a pre-formed object to be appliedagainst the skin without causing irritation and which is miscible withwater. A highly preferred hydrophilic solvent is water itself. Othersuitable hydrophilic solvents include lower alcohols such as ethanol,and polyhydric alcohols such as propylene glycol, butylene glycol,hexylene glycol, glycerin, sorbitol; polyethylene glycols of MW lessthan 30,000, preferably less than 10,000; and polypropylene glycols ofMW less than 5,000, preferably less than 1,000. Advantageously, many ofthe polyhydric alcohols useful as hydrophilic solvents herein alsofunction as humectants for the skin. Further, the hydrophilic solventcan assist in diffusion of skin benefit agents to the skin and, byevaporation from the pre-formed object, can also provide cooling, makingthe pre-formed object more comfortable to wear. Preferred in this latterrespect are solvents which are liquid at 25° C. For topical use,preferably the solvent comprises water and at least one polyhydricalcohol, more preferably, the solvent consists essentially of water andpolyhydric alcohol.

In a preferred embodiment for providing a cosmetic device, thepre-formed object comprises from about 10% to about 99.5% of water, morepreferably from about 20% to about 95%, and yet more preferably fromabout 30% to about 90% of water. Still preferably, the pre-formed objectfurther comprises from about 1.0% to about 50%, preferably from about 5%to about 45%, more preferably from about 10% to about 40% of polyhydricalcohol.

For oral administration use, the solvent is selected from the grouphereinabove that are safe, and preferably pleasing, for oralconsumption.

Gelling Agent

The pre-formed objects of the present invention comprises a gellingagent having a sol-gel transition point between about the melting pointof the solvent and about the boiling point of the solvent. The gellingagent is selected in view of the solvent so that the pre-formed objectcan be manufactured at a safe and economical environment, and also toprovide a pre-formed object that has a stable solid structure at normalstorage temperature. When the solvent comprises water, the sol-geltransition point of the gelling agent is between 0° C. and 100° C.,preferably between about 25° C. and about 80° C., more preferablybetween about 35° C. and about 70° C. The process herein forms thepre-formed object via a thermo transitioning point inherent of thesolvent and the gelling agents. Gelling agents that do not form a solphase in the solvent by elevated temperatures cannot be used in theprocess herein. Mixtures of gelling agents can be used.

The sol-gel transition point of the gelling agent is determined byproviding a sol phase composition using the selected gelling agent andsolvent, and periodically measuring its storage modulus (unit Pa,hereinafter described as G′) and its loss modulus (unit Pa, hereinafterdescribed as G″) as the sol phase composition is cooled. The sol-geltransition point is the temperature where G′ equals G″. Such measurementmethods are well known to those skilled in the art. It is known thatgelling agents of natural origin, particularly gelling agents that aremixtures of natural polymers and have a viscoelastic nature, may providea sol-gel transition point that is not very sharp, or may go throughdistinctive rheological transition points other than at the sol-geltransition point before reaching a complete, stable gel structure. Theprocess of the present invention is particularly useful for providing astable gel structure for pre-formed objects including such gellingagents.

The type and amount of gelling agent to be included in the pre-formedobject is selected according to the desired characteristic and purposeof the product, depending on the properties of the gelling agent.Generally, more gelling agent will provide a more rigid pre-formedobject. For providing food products or orally administrative products,the gelling agent must be edible and acceptable in taste and flavor.Many types of gelling agents are known in the art, including polymericgellants and particulate based gellants such as various types of claysor other silicate based materials. Highly preferred herein are polymericgelling agents that form 3-dimensional gel networks in combination withwater. For providing cosmetic devices, the pre-formed object preferablycomprises from about 0.5% to about 20%, more preferably from about 1% toabout 10%, of gelling agent.

When the polymeric gel forming agents are natural in origin, the gelsmay undergo syneresis, to some degree. In the present invention,stability relates to pre-formed objects that undergo less syneresis,i.e., produces less exudate. Pre-formed objects made by the presentprocess particularly produce less exudates compared to compositions madeby injection molding.

The gelling agents herein may be water soluble or water insoluble, andselected according to the solvent. When the solvent is water orwater-based, preferably the gelling agent is water soluble. Waterinsoluble polymeric gellants such as silicone materials e.g.organopolysiloxane resins, or block co-polymer thermoplastic elastomers,may be used in an appropriate solvent.

The water-soluble polymeric gellants for use in the present inventionare selected from synthetic or natural polymers, and mixtures thereof.Preferred polymers for use herein are natural polymers, includinggelatin, polysaccharides, and mixtures thereof. Preferred arepolysaccharides. The term “polysaccharide” herein means a naturallyoccurring or synthetically produced, linear, branched or cross-linkedpolymer of monosaccharide units, which swells when dispersed in water atlow concentrations and thickens the aqueous phase.

The polysaccharides for use in the pre-formed objects herein arepreferably selected from red seaweed polysaccharides; glucomannans;galactomannans; fermentation polysaccharides, or derivatives thereof;brown seaweed polysaccharides; extracts of marine invertebrates; starch,or derivatives thereof; natural fruit extracts; plant fiber derivatives;kelp; natural plant exudates; and resinous gums; or mixtures thereof.The total polysaccharide level is controlled so that other optionalcomponents of the pre-formed object are not as tightly bound within thegel network and are available for diffusion.

When gelatin is used in the pre-formed objects herein, a high-molecularweight gelatin is combined with a low-molecular weight one to controlthe solubility. A gelatin having a low molecular weight of 20,000 orless has weaker gelling ability when used as the sole gelling agent.

Brown seaweed polysaccharides are isolated by extraction from variousspecies of Phaebophyceae. Suitable brown seaweed polysaccharides for useherein include algin, alginic acid, ammonium alginate, calcium alginate,potassium alginate, sodium alginate, propylene glycol alginate, andmixtures thereof.

Red seaweed polysaccharides are isolated from marine plant speciesbelonging to the class of Rhodophyceae. Red seaweed polysaccharidesprovide mechanical strength to the pre-formed object. Suitable redseaweed polysaccharides for use in the present invention include agarknown in the industry under the (CTFA) trade designation as agar agarflake derived from various Gelidium plant species or closely related redalgae commercially available as “Agar Agar 100” or “Agar Agar 150” fromTIC Gums (Belcamp, Md., USA) or “Agar Agar K-100” from GumixInternational Inc. (Fort Lee, N.J., USA); agarose commercially availableas “Sea Plaque®” from FMC (Philadelphia, Pa., USA) and “Agarose Type1-b” from Sigma-Aldrich Co. Ltd. (Poole, UK); carrageenan, comprisingthe fractions lambda-, iota- and kappa- which are the water extractsobtained from various members of the Gigartinaceae or Solieriaceaefamilies, known in the industry under the (CTFA) trade designation aschondrus, commercially available as “Gelcarin® LA”, “Seakem® 3/LCM”, or“Viscarin® XLV”, all from FMC (Philadelphia, Pa., USA); and furcellarancommercially available from Gum Technology Corporation (Tucson, Ariz.,USA) and Continental Colloids Inc. (Chicago, Ill., USA), or mixturesthereof. Preferably, the red seaweed polysaccharide for use herein isselected from agar, agarose, kappa-carrageenan and furcellaran, ormixtures thereof.

Glucomannans are polysaccharides which comprise an essentially linearbackbone of glucose and mannose residues. Glucomannans have short sidebranches attached to the linear backbone and acetyl groups are randomlypresent at the C-6 position of a sugar unit. The acetyl groups aregenerally found on one per six sugar units to one per twenty sugarunits. Suitable glucomannans or derivatives thereof for use herein havea ratio of mannose to glucose of from about 0.2 to about 3. Preferredglucomannans for use herein include konjac mannan, which is the genericname for the flour formed from grinding the tuber root of theAmorphophallus konjac plant (elephant yam), commercially available underthe trade name “Nutricol® konjac flour” from FMC (Philadelphia, Pa.,USA); and deacetylated konjac mannan; or mixtures thereof.

Galactomannans are vegetable reserve polysaccharides which occur in theendosperm cells of numerous seeds of Leguminosae. The collective term“galactomannan” comprises all polysaccharides which are built up ofgalactose and mannose residues. Galactomannans comprise a linearbackbone of (1→4)-linked β-D-mannopyranosyl units. To these rings areattached as branches, isolated galactopyranose residues byα-(1,6)-glucoside bonds. Galactomannans may in addition also containminor amounts of other sugar residues. Suitable galactomannans for useherein are fenugreek gum; lucern; clover; locust bean gum known forexample in the industry under the (CTFA) trade designation as carob beangum, commercially available as “Seagul L” from FMC (Philadelphia, Pa.,USA); tara gum commercially available from Starlight Products (Rouen,France) or Bunge Foods (Atlanta, Ga., USA); guar gum derived from theground endosperms of Cyamopsis tetragonolobus, commercially available as“Burtonite V7E” from TIC Gums (Belcamp, Md., USA), “Jaguar C” fromRhone-Poulenc (Marietta, Ga., USA), or “Supercol” from Aqualon(Wilmington, Del., USA); and cassia gum commercially available fromStarlight Products (Rouen, France), or mixtures thereof. Preferably, thegalactomannans for use herein have an average one of every 1 to about 5mannosyl units substituted with a (1→6)-linked-α-D-galactopyranosyl unitand are selected from guar gum, locust bean gum and cassia gum, ormixtures thereof.

Fermentation polysaccharides are polysaccharides which are commerciallyproduced by the fermentation of micro-organisms in a medium containing acarbon and nitrogen source, buffering agent, and trace elements.Suitable fermentation poly-saccharides or derivatives thereof, for usein the present invention include gellan gum known in the industry underthe (CTFA) trade designation as gum gellan, a high molecular weighthetero polysaccharide gum produced by a pure-culture fermentation of acarbohydrate with Pseudomonas elodea, commercially available as“Kelcogel” from Kelco (San Diego, Calif., USA); xanthan gum which is ahigh molecular weight hetero polysaccharide gum produced by apure-culture fermentation of a carbohydrate with Xanthomonas campestris,known in the industry under the (CTFA) trade designation as xanthan,commercially available for example as “Keltrol CG1000/BT/F/GM/RD/SF/T/TF”, from Calgon (Pittsburgh, Pa., USA), or“Kelzan” from Kelco (San Diego, Calif., USA); natto gum; pullulan;rhamsan gum; curdlan; succinoglycan; welan gum; dextran, commerciallyavailable as “Sephadex G-25” from Pharmacia Fine Chemicals (Piscataway,N.J., USA) and derivatives thereof; and sclerotium gum, commerciallyavailable as “Amigel” from Alban Muller International (Montreil,France), or mixtures thereof. Preferred fermentation polysaccharides orderivatives thereof are selected from gellan gum and xanthan gum, ormixtures thereof. More preferably the fermentation polysaccharide orderivative thereof is xanthan gum.

Extracts of marine invertebrates can also be used. Polysaccharidesderived from marine invertebrates, specifically the exoskeleton of suchinvertebrates, consist chiefly of N-acetyl-D-glucosamine residues.Examples of such polysaccharides suitable for use herein includechitosan, commercially available for example as “Marine Dew” fromAjinomoto (Teakneck, N.J., USA); and hydroxypropyl chitosan commerciallyavailable for example as “HPCH Liquid” from Ichimaru Pharcos (YamagataGun Gifu-Pref, Japan) and derivatives; or mixtures thereof.

Starches are polysaccharides which consist of various proportions of twoglucose polymers, amylose and amylopectin. Suitable materials for useherein include starch, amylopectin and dextrin, commercially availableas “Nadex 360” from National Starch (Bridgewater, N.J., USA), andderivatives or mixtures thereof. Examples of natural fruit extractssuitable for use herein include pectin, arabian and mixtures thereof. Asuitable example of a plant fiber derivative for use herein iscellulose. Suitable polysaccharides obtained from natural plant exudatesfor use herein include karaya, tragacanth, arabic, tamarind, and ghattygums, or mixtures thereof. Examples of resinous gums suitable for useherein include shellac gum, which is obtained from the resinoussecretion of the insect Laccifer (Tachardia) lacca, damar gum; copal gumand rosin gum; or mixtures thereof.

Natural and synthetic polymeric gelling agents that form gels incombination with other substances may also be used as a gelling agent incombination with other thermo-forming gelling agents, so long as the gelphase forming can been synchronized. They may be chemically crosslinked. Some gelling agents form gels in combination with substancessuch as sugar, alcohol, or mono- or multi-valent salts. Mono- ormulti-valent salts may additionally act as gel strengthening agentsimparting added strength to the pre-formed objects herein. Suitablecations for such salts can be selected from potassium, sodium, ammonium,zinc, aluminium, calcium and magnesium ions, or mixtures thereof.Suitable anions associated with the aforementioned cations may beselected from chloride, citrates, sulfate, carbonate, borate andphosphate anions, or mixtures thereof.

Physical cross linking refers to polymers having cross links which arenot chemical covalent bonds but are of a physical nature such that thereare areas having high crystallinity or areas having a high glasstransition temperature. Such cross linked polymers may also be used.Preferably, the polymer is chemically cross linked thermally. Inaddition when chemical cross links are formed in the system, apolyfunctional cross linker and/or a free radical initiator may bepresent in the premix to initiate the cross linking upon irradiation.

Preferably, the pre-formed objects herein comprise a mixture ofwater-soluble polymeric gelling agents of natural origin. A preferredwater-soluble polymeric gelling agent mixture herein may comprise apolysaccharide and a non-ionic water-soluble polymer or, alternatively,it may comprise two polysaccharides. More preferably, the water-solublepolymeric gel forming agent is a polysaccharide mixture, wherein thepolysaccharide mixture comprises (1) at least one red seaweedpolysaccharide; brown seaweed polysaccharide; or mixtures thereof; and(2) at least one fermentation polysaccharide; galactomannan;glucomannan; natural plant exudate; or natural fruit extract; andderivatives or mixtures thereof. Even more preferably, the water-solublepolymeric gel forming agent of the pre-formed objects of the presentinvention is a polysaccharide mixture comprising (1) at least one redseaweed polysaccharide; and (2) at least one fermentationpolysaccharide; glucomannan; or galactomannan; and derivatives ormixtures thereof.

In a preferred embodiment, the water-soluble polymeric gel forming agentof the present invention is a polysaccharide mixture, comprising a redseaweed polysaccharide and a glucomannan or a galactomannan. The ratioof red seaweed polysaccharide to glucomannan or galactomannan in thepolysaccharide mixture is preferably from about 20:1 to about 1:5 andmore preferably from about 10:1 to about 1:2. Without being limited bytheory, it is believed that gel compositions herein form 3-dimensionalnetworks or matrices which bind or encapsulate other ingredients of thecomposition. Further, it has been found that this highly preferredpolysaccharide mixture has a sol-gel transition point at between about35° C. and about 70° C. that is not very sharp, and has a seconddistinctive Theological transition point at between about 20° C. andabout 50° C. It has been found that the composition comprising thehighly preferred polysaccharide mixture forms a stable gel structureafter being cooled below such second transition point. The process ofthe present invention is particularly useful for such highly preferredpolysaccharide mixture. In a highly preferred embodiment, the gel phasecomposition is cooled well below the second transition point in thecooling process. By cooling the gel phase composition to such extent, apre-formed object having stability in terms of gel strength,flexibility, and reduced exudates is obtained.

Cosmetic Device

In a highly preferred embodiment, the pre-formed object of the presentinvention is a sheet-like cosmetic device for delivering skin benefitagents to the skin hair or nails. Herein, the term “pre-formed sheet” isused to describe such sheet-like pre-formed object. A pre-formed sheetis a preferable embodiment of the pre-formed object herein.

The cosmetic device of the present invention comprises a pre-formedsheet made by the process described below, and may further comprise acoating composition. The coating composition may be included in the samepackage as the pre-formed sheet to reach equilibrium in the package.Such application step of the coating composition onto the pre-formedsheet may be disposed in a continuous manner of making the cosmeticdevice.

Cosmetic devices according to the present invention are generally of asize such that each surface has an area of from about 0.25 cm² to about1,000 cm², preferably from about 1 cm² to about 300 cm². Surface arearefers to that of a flat plane having the same boundary as the surfacei.e. ignoring any surface texturing present.

The cosmetic devices herein can be, for example, square, circular,semicircular, rectangular, oval, rings, crescents, teardrops or othermore complex shapes which may be composites of these, for covering areassuch as the eye area, eye lids, the nose, the mouth area, the forehead,the chin, the entire contour of the face, or combinations thereof.

Coating Compositions

In the pre-formed sheet of the present invention, the first surface isat least partially coated with a discrete coating composition comprisingat least one skin benefit agent for the skin, hair or nails. By“discrete” coating composition is meant one that is applied to thepre-formed sheet as a distinctly different composition, in particularone having a different chemical constitution which is separatelyprepared from the pre-formed sheet and is laid down as a separate layer,before, after or at the same time as the formation of the pre-formedsheet. The coating composition allows more efficient delivery of skinbenefit agents to the skin and affords greater formulation flexibility.

The coating composition comprises at least one skin benefit agent forthe skin, hair or nails. Preferably, the pre-formed sheet and thecoating composition each comprise at least one skin benefit agent incommon. In this way, whilst the coating composition can rapidly providea skin benefit agent to the target area, the pre-formed sheet can act asa reservoir for the skin benefit agent or inhibit the pre-formed sheetfrom absorbing the skin benefit agent from the coating composition.

Skin Benefit Agents

In a highly preferable embodiment, the cosmetic device of the presentinvention comprises a coating composition which comprises at least oneskin benefit agent for the skin hair, or nails. The solid pre-formedsheet preferably also comprises one or more of such skin benefit agents.The term “skin benefit agent” as used herein, means an active ingredientwhich provides a cosmetic and/or therapeutic effect to the area ofapplication on the skin, hair, or nails. The skin benefit agents usefulherein include anti-acne agents, emollients, non-steroidalanti-inflammatory agents, topical anaesthetics, artificial tanningagents, antiseptics, anti-microbial and anti-fungal actives, skinsoothing agents, sunscreening agents, skin barrier repair agents,anti-wrinkle agents, anti-skin atrophy actives, lipids, skin lighteningagents, sebum inhibitors, sebum inhibitors, skin sensates, proteaseinhibitors, skin tightening agents, anti-itch agents, hair growthinhibitors, desquamation enzyme enhancers, anti-glycation agents, andmixtures thereof.

In general, the coating compositions of the present invention comprisefrom about 0.01% to about 60%, preferably from about 0.1% to about 40%and most preferably from about 0.5% to about 30% by weight of thecoating compositions of at least one skin benefit agent, or mixturesthereof.

Preferred examples of skin benefit agents useful herein include thoseselected from the group consisting of ascorbic acid and derivativesthereof, salicylic acid, niacinamide, panthenol, tocopheryl nicotinate,benzoyl peroxide, 3-hydroxy benzoic acid, flavonoids (e.g., flavanone,chalcone), farnesol, phytantriol, glycolic acid, lactic acid, 4-hydroxybenzoic acid, acetyl salicylic acid, 2-hydroxybutanoic acid,2-hydroxypentanoic acid, 2-hydroxyhexanoic acid, cis-retinoic acid,trans-retinoic acid, retinol, retinyl esters (e.g., retinyl propionate),phytic acid, N-acetyl-L-cysteine, lipoic acid, tocopherol and its esters(e.g., tocopheryl acetate), azelaic acid, arachidonic acid,tetracycline, ibuprofen, naproxen, ketoprofen, hydrocortisone,acetominophen, resorcinol, phenoxyethanol, phenoxypropanol,phenoxyisopropanol, 2,4,4′-trichloro-2′-hydroxy diphenyl ether,3,4,4′-trichlorocarbanilide, octopirox, lidocaine hydrochloride,clotrimazole, miconazole, ketoconazole, neomycin sulfate, theophylline,and mixtures thereof.

For cosmetic methods of treatment of the skin, hair or nails, thecosmetic skin benefit agent is preferably selected from anti-wrinkle andanti-skin atrophy actives, anti-acne actives, artificial tanning agentsand accelerators, emollients, humectants, skin repair actives, skinbarrier repair aids, skin lightening agents, skin sensates, skinsoothing agents, lipids, sebum inhibitors, sebum stimulators,sunscreening agents, protease inhibitors, skin tightening agents,anti-itch ingredients, and desquamation enzyme enhancers, or mixturesthereof.

The pH of the pre-formed sheets and coating compositions herein ispreferably from about 3 to about 9, more preferably from about 4 toabout 8. The pH may be selected depending on the activity of the skinbenefit agent.

Process of Manufacturing the Pre-Formed Object

The process for making a pre-formed object having a plurality ofsurfaces of the present invention relates to a continuous line processcomprising the steps of:

-   -   (1) providing a sol phase of the composition comprising a        solvent and a gelling agent having a sol-gel transition point        between about the melting point of the solvent and about the        boiling point of the solvent;    -   (2) forming surfaces of the sol phase composition by passing        through a surface forming system, the surface forming system        pressing the sol phase composition between a plurality of        liners;    -   (3) cooling the sol phase composition into a gel phase; and    -   (4) cutting the gel phase composition;    -   wherein the pre-formed object is free of a supporting substrate.

The process of the present invention relates to forming the pre-formedobject via cooling. The process herein is suitable for providing acontinuous flow of material for making the pre-formed object, and thuscan be suitably applied to large scale manufacturing. The process hereinmay be used for making pre-formed objects comprising any gelling agenthaving a sol-gel transition point, however, is particularly useful forgelling agents that do not have a sharp sol-gel transition point, orhave rheological transfer points other than the sol-gel transitionpoint. In this respect, the process herein is particularly useful formaking pre-formed objects comprising a mixture of gelling agents ofnatural source.

The present invention further relates to a continuous line process formaking a pre-formed sheet having a first surface and a second surfacecomprising the steps of:

-   -   (1) providing a sol phase composition of the pre-formed sheet        comprising:        -   (a) from about 10% to about 99.5% water; and        -   (b) from about 0.5% to about 20% polysaccharide gelling            agent having a sol-gel transition point between about 25° C.            and about 80° C.;        -   wherein the sol phase composition is heated to a temperature            of at least 5° C. higher than the sol-gel transition point;    -   (2) pre-cooling the sol phase composition to a temperature of        between 0° C. and 5° C. higher than the sol-gel transition        point;    -   (3) forming the first and second surfaces by pressing the sol        phase composition between two liners, the two liners being        supplied by two counter-rotating rollers facing each other,        wherein the rollers further comprise cooling means, wherein the        two liners further provide textures to the first and second        surfaces;    -   (4) cooling the sol phase composition into a gel phase by        cooling to no higher than 20° C.; and    -   (5) cutting the gel phase composition by a die;    -   wherein the pre-formed sheet is free of a supporting substrate        and the pre-formed sheet has a flex angle of from about 15° to        about 80°.

In a preferred continuous line process, all of the manufacturing stepsfrom sol phase making to finished product packaging are disposed in acontinuous line with speed buffer means and transfer means to carrymaterial to a different line, as necessary.

The present invention further relates to a process for providing apackaged cosmetic device comprising: a pre-formed sheet and a coatingcomposition comprising a skin benefit agent; comprising the steps of:

-   -   (1) providing a unsealed package;    -   (2) applying the coating composition in the package;    -   (3) placing the pre-formed sheet in the package; and    -   (4) sealing the package;        wherein the steps are in communication with each other to        provide a continuous line process.

As the preferred pre-formed sheets herein utilize water as the solvent,the pre-formed sheet is relatively vulnerable to change of humidity,particularly excessive or rapid drying. Drying beyond a certain extent,depending on the composition, will decompose or deform the pre-formedobject by destroying its gel structure. Therefore, in the processherein, it is advantageous to dispose the packaging means for thecosmetic device such that the pre-formed sheet is immediately packagedand sealed after production.

FIG. 1 schematically depicts a process, in functional perspectives, formaking a preferred cosmetic device embodiment comprising a pre-formedsheet having a composition selected from one of Table 1 and a coatingcomposition selected from one of Table 2, wherein the cosmetic device ispackaged in a blister package.

While the process of the present invention may be used to form anynumber of surfaces, the process for making a pre-formed sheet having afirst surface and a second surface for the preferred cosmetic deviceembodiment is illustrated herein.

TABLE 1 Compositions for Pre-formed Sheet Ingredient % w/w % w/w % w/w %w/w Agarose 0.3 0.8 1.6 1.5 Agar 0.60 — — — Kelgum (Kelco)¹ — 0.5 0.80.75 Keltrol T (Kelco)¹ 0.2 — — — Locust Bean Gum 0.2 — — — Niacinamide— 5.0 8.0 10.0 D-Panthenol 5.0 — 2.0 1.0 Glycerin 10.0 15.0 10.0 10.0Disodium EDTA — 0.10 0.10 0.10 Butylene Glycol — 5.0 — — Hexylene Glycol3.0 — 5.0 5.0 Ethyl Paraben 0.20 0.15 0.15 0.15 Water to 100% to 100% to100% to 100%

TABLE 2 Coating compositions Ingredient % w/w % w/w % w/w % w/w % w/wKelgum (Kelco)¹ 0.1 — — — — Keltrol T (Kelco)¹ — 0.5 0.9 — 0.8 Locustbean gum 0.4 — — — — Polyacrylamide, iso- — — — 2.75 — paraffin &laureth-7 Niacinamide 5.0 — 8.0 3.5 10.0 D-Panthenol — 5.0 2.0 2.0 1.0Glycerin — 5.0 10.0 9.0 10.0 Disodium EDTA 0.10 0.1 0.1 0.1 0.1 Butyleneglycol — 5.0 — — — Hexylene glycol — — 5.0 — 5.0 Tospearl ™ 145² — — 6.01.0 7.5 DC 2-1559 emulsion³ — — 3.0 4.0 3.0 Magnesium ascorbyl 3.0 — — —— phosphate Tocopheryl acetate 0.5 — — 0.75 — PEG-60 hydrogenated 1.50 —— — — castor oil Cetyl alcohol — — — 1.5 — Stearyl alcohol — — — 1.0 —Lonzaine ™ 16SP⁴ 0.47 — — — — Tinoderm ™ E⁵ — — — — 10.0 Sucrose cocoate— — — 1.0 — and sorbitan stearate⁶ Isohexadecane — — — 2.0 — Isopropyliso- — — — 1.0 — stearate SEFA cottonate — — — 1.0 — Petrolatum — — —3.0 — Water, fragrance, to 100% preservatives ¹Kelgum and Keltrol T are,respectively, a 1:1 mixture of xanthan gum and locust bean gum; andxanthan gum, supplied by Kelco, San Diego, CA, USA.²Polymethylsilsesquioxane from Toshiba ³Dimethicone, dimethiconol,laureth-4, laureth-23, and water; from Dow Corning ⁴Water and cetylbetaine from Lonza ⁵Water, tocopheryl acetate, polysorbate 80,caprylic/capric triglyceride and lecithin from CIBA ⁶Arlatone 2121 fromICI

Referring to FIG. 1, the process of the present invention for making thepre-formed sheet is generally described as the pre-formed sheet makingline. The coating composition is prepared separately, and supplied tothe cosmetic device packaging line, wherein the unsealed blister packagereceives the coating composition, followed by receiving the transferredpre-formed sheet, to make a cosmetic device. The cosmetic device is thensealed. The blister package is typically supplied in plurality as acontinuous sheet of thermoformed material. After the cosmetic device isreceived and sealing is provided, the continuous packaging material iscut into unit application forms. The pre-formed sheet making line isdepicted in detail in FIG. 2.

Referring to FIG. 2, the process of the present invention starts byproviding a sol phase of the composition, in this embodiment, thecomposition of one of Table 1. The sol phase making step (10) istypically conducted by mixing the components of the pre-formed sheet ina tank (11) at a temperature well above the sol-gel transition point,preferably at least 5° C. higher than the sol-gel transition point. Inthis embodiment, the sol phase making is conducted at elevatedtemperature with the aid of stirring (12). The stirring is kept to adegree so that the structures of the polymeric gelling agents per se arenot destroyed.

Preferably, the sol phase composition is pre-cooled before being sent tothe sheet forming system. In the pre-cooling step (13), the sol phasecomposition is cooled to a temperature still above, but closer to thesol-gel transition point, for example by means of placing in a pre-sheetforming tank (14). Preferably, the sol phase composition is cooled to atemperature of between 0° C. and 5° C. higher than the sol-geltransition point. It has been found that, with the aid of stirring (15),the sol phase composition can retain the sol phase at the sol-geltransition point temperature.

The pre-cooled sol phase composition is then delivered to the surfaceforming system, in this embodiment, the sheet forming system (20). Thesheet forming system is preferably a mechanical pressuring of the solphase composition against two hard surfaces facing each other, such ascounter-rotating rollers or plates facing each other. Passing of the solphase system through counter-rotating rollers are preferred in that itallows continuous flow of the line. When a pair of opposing plates isused for the surface forming system, the continuity of flow can beprovided by allowing intervals during the pressing of a given area for adetermined period of time. In this embodiment, the sol phase compositionis poured at a controlled rate between the first liner (22) and thesecond liner (23) supplied by two counter-rotating rollers (21) whichsupply the liners.

FIG. 3 is a schematic view of a preferred embodiment of the surfaceforming system of the present invention, with the thickness of theliners and depths of textures inflated. Referring to FIG. 3, the solphase composition (200) which is in a fluid state is directed betweenthe first liner (202) and the second liner (203), wherein mechanicalpressure is applied to the sol phase composition by the rotating actionof the rollers. In order to direct the sol phase composition to theengaging point of the rotating rollers, the sol phase composition may bepoured at the engaging point, or poured at one of both of the liners tobe delivered to the engaging point. In this embodiment, the sol phasecomposition travels vertically in the surface forming system, however,the surface forming system may also be configured horizontally.Preferably the first liner is textured to provide a non-planertopography, more preferably the second liner is further textured toprovide a non-planer topography. In this embodiment, both liners providetextures of regular frequency. Such textures are transferred to the solphase composition via mechanical pressure applied to the sol phasecomposition (212, 213), and preferably by further cooling of the solphase composition while passing the liners in contact with thecounter-rotating rollers, wherein the rollers (201) encompass a coolingmeans, typically a continuous running of cold water. As the liners areunwound from the counter-roating rollers, the partially formed sol phasecomposition which is adhered to the two liners are released from thepressure of the counter-rotating rollers, to travel to the next step.

The liners herein are thin enough to provide effective cooling, whilethick enough to retain its mechanical strength and texture definitionthrough the process. The material for the liners are selected in view ofheat conductivity, rigidity, elasticity, adhesion to the sol phasecomposition, and inertness of the gel phase composition. In thisembodiment, preferred liners are made of polyethylene and have athickness of from about 10 μm to about 50 μm. Referring to FIG. 2, whentextured liners are used, the liners may be formed to the desiredtexture by a pressing against an embossing roller (24) with the aid ofheat prior to supplying to the surface forming system. The embossingprocess for the liners may be conducted discontinuous to the lineprocess herein. The same may be applied to the second liner.

The preferred surface forming system herein is advantageous in many waysfor providing pre-formed sheets having textured surfaces, free of asupporting substrate. For example, the sol phase composition would beeffectively cooled so that at least the surfaces of the composition incontact with the liners would quickly transition to a harder state orpartial gel phase, thereby ensuring well defined textures at thesurfaces. Further, control of the overall line flow of the compositionis improved, as the gelled or solidified surface would be lesssusceptible to process vibration and movement of the liner. Further, theentire process line can be rationalized, as less subsequent coolingwould be necessary, thereby leading to shorter lines or faster process.The speed in which the sol phase composition passes the surface formingsystem is carefully adjusted so that the surfaces are soft enough to betextured, but having solid enough surfaces after leaving the system.

In the process herein, the composition which is partially gelled orgelled only in local areas, particularly the surfaces, are defined as asol phase composition. It is typical that the composition leaving thesurface forming system is still a sol phase composition, even if thesurface of the composition is below the sol-gel transition point.

The process of the present invention provides stable pre-formed sheetshaving a thickness of about 0.1 mm to about 5 mm with relatively deeptexture depths, as deep as about 10 μm to about 500 μm, depending on thethickness of the pre-formed sheet. In a particularly preferredembodiment, the pre-formed sheet has a thickness of about 0.5 mm toabout 2.0 mm, and a texture depth of from about 50 μm to about 200 μm atthe first and second surfaces. Such specific texturing of the surfacesmay provide various advantages to the cosmetic device comprising thepre-formed sheet, which are described below.

Referring to FIG. 2, the partially solidified sol phase composition,which may be partially gelled, is then directed to the cooling system(30) for completely transitioning the composition into a gel phase. Inthis embodiment, the cooling is achieved by direct cooling such as bycooling plates (31) and chilled rollers (32), and additionally byindirect cooling such as by placing the line in a cooling chamber (33).In this embodiment, the composition is cooled to the extent the entiresheet is transitioned to a complete stable gel phase.

The speed of cooling at the surface forming step and the cooling stepare important factors of the process herein for obtaining a stable gelphase for the pre-formed sheet. The speed will depend on the compositionfor the pre-formed sheet, particularly on the rheological behaviors ofthe composition during the process. For this embodiment, the rate ofcooling is preferably from about 5° C. to about 100° C. per minute, morepreferably from about 10° C. to about 50° C. per minute. Generally, thespeed of cooling is much faster when the pre-formed sheet is made byinjection molding processes. Particularly for pre-formed sheetembodiments that use natural gelling agents, the slower cooling achievedin the process herein is beneficial for providing a stable product.

The gel phase composition thus obtained is then cut (40) into itspredetermined size and shape to obtain the pre-formed sheet. The linerin contact with the second surface may be removed (42) prior to thecutting step. The liner in contact with the first surface is preferablykept intact until after the cutting step. The cutting can be conductedby any means known in the art. For effective cutting in a continuousline process, cutting is preferably conducted by vertical movement of adie, preferably by rotating a roller having the dies disposed on thesurface (41). The preferred cutting step of the present invention isalso advantageous for effectively providing pre-formed sheets havingrelatively deep texture depths on the first surface. In the preferredembodiment for making a cosmetic device, both surfaces of the pre-formedsheet are textured in a regular pattern.

FIG. 4 is a schematic view of a preferred embodiment of the cuttingsystem of the present invention, with thickness of the liners inflated.Referring to FIG. 4, the blades of the die (401) enter from the secondsurface toward the edge of the first surface (402) for verticallycutting the pre-formed sheet. The extent of cutting is so controlledthat the edge of the blade of the die (403) reaches beyond the bottom(404) of the texture of the first surface, however, does not reachbeyond the peak (405) of the texture of the first surface. It has beensurprisingly found that, even when the edge of the die blade does notcompletely cut the thickness of the sheet such as in the area shown as406, such area can be cut without additional process steps. The area406, where the die blade does not reach, is cut by the shear applied bythe movement of the die blade, or by forcing the pre-formed sheet totear off upon transferring the pre-formed sheet, or both, withoutaffecting the shape or stability of the obtained pre-formed sheet.

Referring to FIG. 2, the finally obtained pre-formed sheet is furthertransferred for packaging by, for example, an arm with suction means(51) which removes the pre-formed sheets away from the liner in contactwith the first surface. Effective and convenient packaging can beconducted by releasing the sucked pre-formed sheet and placing into thepackage, followed by sealing of the package. In this embodiment, thepre-formed sheet is placed into a blister package in this manner,wherein the first surface remains the lower surface in the package, thesecond surface to face the sealing of the package.

The coating composition for the cosmetic device is separately made. Avariety of methods are suitable for applying the coating to thepre-formed sheet in order to form the finished cosmetic device. Forexample, the coating may be applied directly to the pre-formed sheete.g. dispensed via a pipette to provide ‘dots’ of coating or spread witha brush to provide an uniform layer. Alternatively, the coating may beapplied using screen printing techniques or via an extrusion process.The coating may also be applied to the pre-formed sheet via an indirectprocess. Referring to FIG. 1, in this embodiment, the coatingcomposition is applied to a surface of the blister package, and then thepre-formed sheet is placed on top of the coating composition. A varietyof methods may be used to apply the coating to the packaging material.These include air atomised spraying of the coating, dot deposition ofthe coating via a nozzle cosmetic device or an electrofluidic coatingprocess of the type used in ink jet printing. A preferred method is dotdeposition of the coating composition into a packaging tray usingnozzles, swirling the nozzles to provide an uniform layer of coating,then pressing the pre-formed sheet onto the top of the coatingcomposition.

The packages for the cosmetic device embodiment herein is made ofmaterials which have low water vapor permeability to minimize drying outof the cosmetic device during storage. Any suitable material can be usedfor the packaging such as plastics materials and foil laminates. Thisprotection can be provided by a substrate or by a release liner such asa plastic film, which provides easy release upon using the cosmeticdevice.

An embodiment of the pre-formed sheet for the cosmetic device made bythe process of the present invention is shown in perspective in FIG. 5wherein the first surface is shown on top. The pre-formed sheet isbroadly crescent shaped, of dimensions such that a notional rectangle of4 cm×2 cm bounds the crescent, and the first surface has repeatingdiamond shaped convexes which provide a distinct texture. Provided insection view as in FIG. 7, the cosmetic device (1) comprises apre-formed sheet (2) and coating composition (3) on a first surface (4)of the pre-formed sheet. The pre-formed sheet is generally flat having auniform thickness. The pre-formed sheet has a second surface (5) opposedto the first surface (4). The pre-formed sheet by the process hereindoes not have distinct rims at the peripheral. However, it has beensurprisingly found that, even without the rims, the pre-formed sheet ofthe present invention provides enough strength to the cosmetic devicefor handling at regular conditions.

Key parameters for evaluating the physical characteristics of theobtained cosmetic device are gel strength and flexibility. Flexibilityfor the cosmetic device herein is measured by how much the device bendsunder its own weight when it overhangs an edge at its most flexiblesurface. Minimum required gel strength is confirmed by checking if thedevice does not rupture under its own weight when overhanging. A 4 cm by2 cm rectangular, test strip of the pre-formed sheet is prepared. Forcosmetic devices of the present invention which comprise the pre-formedsheet and a coating composition, the test strip should be evenly coatedwith the coating composition at a rate of 0.015 g/cm², and should bemeasured at 25° C. The strip, coated first surface uppermost, issupported on a flat surface, having a rectangular edge so that 2 cm ofthe 4 cm length of the strip can overhang without obstruction. Thearrangement is shown schematically in FIG. 8. Test strip (6) (coatingcomposition not shown) overhangs the vertical edge of solid support (7),whose upper surface is horizontal. The angle θ of overhang from thevertical is measured by drawing a straight line (shown as a dashed linein FIG. 8) from the tip of the gel sheet to the edge of the support.This can conveniently be done from a photograph. The test strip shouldnot rupture upon overhanging. The angle of overhang, θ, is the flexangle of the composition. The test strip should have a flex angle offrom about 15° to about 80°, preferably from about 25° to about 75° andmore preferably from about 40° to about 60°.

The present invention further relates to a cosmetic device comprising:

-   -   (1) a pre-formed sheet comprising:        -   (a) from about 10% to about 99.5% water; and        -   (b) from about 0.5% to about 20% polysaccharide gelling            agent having a sol-gel transition point between about 25° C.            and about 80° C.;    -   wherein the pre-formed sheet is free of a supporting substrate,        has a thickness of from about 0.1 mm to about 5 mm, preferably        from about 0.5 mm to about 2.0 mm and a first surface and a        second surface, the first surface having a repeating texture        having a depth of from about 10 μm to about 500 μm, preferably        from about 50 μm to about 200 μm at a frequency of from about        0.2 to about 1 per mm, preferably from about 0.3 to about 0.7        per mm; wherein the depth of the texture is at least about 10%        of the thickness of the pre-formed sheet; and    -   (2) a coating composition comprising a skin benefit agent and        having a viscosity of from about 1000 mPa·s to about 30,000        mPa·s, preferably from about 5000 mPa·s to about 15,000 mPa·s;    -   wherein the repeating texture is so designed to provide a        network of channels that allows fluid communication of the        coating composition when the first surface is worn on the skin.

Preferred embodiments of the pre-formed sheet compositions are describedin Table 1 above. More preferably, the pre-formed sheets are made by theprocess described above.

The coating composition can be aqueous solutions, including gels, oremulsions such as oil-in-water emulsions, water-in-oil emulsions ormultiple emulsions having aqueous or oily external phases. Preferredembodiments are described in Table 2 above, all of which have aviscosity of between about 5000 mPa·s and about 15,000 mPa·s. Theviscosity of the coating composition is measured on a Brookfieldviscometer using a heliopath T-bar C spindle at 5 rpm.

The weight ratio of the coating composition to the pre-formed sheet isgenerally more than about 1:50, preferably from about 1:25, morepreferably from about 1:15 to about 10:1. Preferred dosage rates of thecoating compositions on the pre-formed sheet can alternatively beexpressed as from about 0.001 to about 0.2 g/cm², preferably from about0.005 to about 0.05 g/cm². Generally, the coating composition covers atleast about 20%, preferably at least about 50%, more preferably at leastabout 75% of the area of the first surface.

The cosmetic device herein can be made by any suitable process,preferably, by the process as described herein. In the embodiment above,the pre-formed sheet is placed into a blister package so that the firstsurface remains the lower surface in the package, the second surface toface the sealing of the package. Such packaging is advantageous for thecosmetic device herein. It is the intention that the wearer would removethe cosmetic device from the packaging with the fingers engaging thesecond surface, and then applying the first surface to the skin.

It has been surprisingly found that, by providing a certain thickness tothe pre-formed sheet, and texture of certain depth and frequency to thefirst surface of the pre-formed sheet, the cosmetic device providesvarious benefits for the wearer of the cosmetic device. FIG. 6 is anenlarged, partially segmented perspective view of the first surfacevicinity of a preferred embodiment of the pre-formed sheet of thepresent invention. Referring to FIG. 6, the first surface of thepre-formed sheet has a repeating texture that provides a network ofchannels (601). Despite the cosmetic device comprises a coatingcomposition (not shown) of low viscosity, the pre-formed sheet can beconveniently adhered to the skin by applying the first surface to theskin. It has been surprisingly found that, with the elements above, thecosmetic device provides adequate adhesion to the skin such that, evenwhen worn in a vertical manner, the cosmetic device does not easily dragdown the skin. Without being bound by theory, it is believed that thenetwork of channels that allow fluid communication of the coatingcomposition provides an even distribution of the coating compositionpredominantly in the channels of the texture, thereby allowing theremaining wearer contacting area (610) of the texture to effectivelyadhere to the skin.

Referring to FIG. 5, a highly preferred embodiment of the wearercontacting areas is depicted as the plurality of diamond shapedconvexes. Referring back to FIG. 6, when the coating composition isexcess the amount that can be carried in the channels, the network ofchannels also allows discretion of the coating composition to theperipheral (602) of the pre-formed sheet thereby allowing the coatingcomposition to flow away from, or evaporate from the area of the skin onwhich the cosmetic device is applied. Thus, after the cosmetic device isworn on the skin, the coating composition immediately evenly distributesthroughout the area on which the cosmetic device is worn, leaving thediscontinuous, spaced wearer contacting areas more or less vacuum. Thus,the cosmetic device is sucked onto the skin. For such effective suckingof the cosmetic device on the skin, the pre-formed sheet is preferablyuniform in thickness. The channels further provide a reservoir of thecoating composition between the pre-formed sheet and the skin, thusallowing continuous contact of the coating composition to the skin sothat the skin benefit agents are effectively delivered to the skin.

Providing rims around the peripheral of the pre-formed sheet has beenproposed for increasing the strength of the pre-formed sheet. If the rimis overly distinct such that it interferes with the fluid communicationof the channels, the rims may negatively affect the suction effectherein. Thus, when rims are provided to the pre-formed sheet, they arekept to a modest thickness and in a manner that provide continuity tothe channels.

Preferably, the second surface of the pre-formed sheet also has arepeating texture having a depth of from about 10 μm to about 500 μm,preferably from about 50 μm to about 120 μm at a frequency of from about0.2 to about 1 per mm, preferably from about 0.3 to about 0.7 per mm.Texturing on the second surface is also advantageous to the wearer. Thefirst surface is intended to be applied to the skin. Upon removing thecosmetic device from the package, the wearer would engage the fingers onthe second surface. The texturing of the second surface will help thisengagement. Further, even if the wearer applies the second surface onthe skin, the texturing of the second surface will provide similareffects as expected by the first surface. Further, from an aestheticpoint of view, texturing on both surfaces provides a matte, less shinyappearance to the cosmetic device, thereby the cosmetic device is moreor less invisible upon application to the skin.

Methods of Use

The cosmetic device of the present invention is applied to a target areaof the skin, hair or nails, and will generally be left on the targetarea for at least 1 minute, preferably at least 5 minutes, it can beleft on for a period of up to 12 hours, preferably up to 3 hours, morepreferably up to 1 hour, though most preferably for less than 30minutes. The cosmetic device can then be removed in one piece.Preferably, the first surface is worn on the skin.

In one embodiment, the cosmetic device may comprise the coatingcomposition in excess amount, wherein the excess coating composition isfirst applied to the entire surface of the face, followed by applyingthe cosmetic device to a specific area of the face where intensivetreatment is desired.

Depending on the skin benefit agent contained therein, the pre-formed,cosmetic devices of the present invention may have at least one of thefollowing uses; hydrating the skin, hair or nails, smoothing fine linesand wrinkles; cosmetically treating acne; firming or softening the skin,strengthening; softening; exfoliating; improving and/or evening skintone and/or texture; skin, hair or nail lightening; tanning; reducingthe appearance of pores; absorbing or controlling secretions; protectingand/or soothing the skin, hair or nails, muscles, aches or pains;reducing puffiness, and/or dark circles; stimulating wound healing;warming, refreshing or cooling the skin, hair or nails; relievinginflammation; brightening the complexion; decongesting; reducingswelling; treating dermatological conditions; cushioning; purifying;fragrancing; reducing bacterial or micro-organism growth; healing;repelling insects; removing unwanted hair, dirt, or make-up; andcoloring or bleaching the target area to which the cosmetic device isapplied. Preferably, the pre-formed sheets herein are cosmetically usedfor hydrating the skin, hair or nails; smoothing fine lines andwrinkles; improving and/or evening the skin tone and/or texture; andfirming or softening of the skin.

It is understood that the foregoing detailed description of examples andembodiments of the present invention are given merely by way ofillustration, and that numerous modifications and variations may becomeapparent to those skilled in the art without departing from the spiritand scope of the invention; and such apparent modifications andvariations are to be included in the scope of the appended claims.

All documents cited in the Detailed Description of the Invention are, inrelevant part, incorporated herein by reference; the citation of anydocument is not to be construed as an admission that it is prior artwith respect to the present invention.

While particular embodiments of the present invention have beenillustrated and described, it would be obvious to those skilled in theart that various other changes and modifications can be made withoutdeparting from the spirit and scope of the invention. It is thereforeintended to cover in the appended claims all such changes andmodifications that are within the scope of this invention.

1. A cosmetic device comprising: a) a pre-formed sheet comprising: i.from about 10% to about 99.5% water; and ii. from about 0.5% to about20% polysaccharide gelling agent having a sol-gel transition pointbetween about 25° C. and about 80° C.; wherein the pre-formed sheet isfree of a supporting substrate, has a thickness of from about 0.1 mm toabout 5 mm, and a first surface and a second surface, the first surfacehaving a repeating texture having a depth of from about 10 μm to about500 μm at a frequency of from about 0.2 to about 1 per mm, wherein thedepth of the texture is at least about 10% of the thickness of thepre-formed sheet; and b) a coating composition comprising a skin benefitagent and having a viscosity of from about 1000 mPa·s to about 30,000mPa·s; wherein the repeating texture is so designed to provide a networkof channels that allows fluid communication of the coating compositionwhen the first surface is worn on the skin.
 2. The cosmetic device ofclaim 1 wherein: a) the thickness of the pre-formed sheet is from about0.5 mm to about 2.0 mm; b) the repeating texture has a depth of fromabout 50 μm to about 200 μm at a frequency of from about 0.3 to about0.7 per mm; and c) the coating composition has a viscosity of from about5000 mPa·s to about 15,000 mPa·s.
 3. The cosmetic device of claim 2wherein the second surface has a repeating texture.